app/src/components/Seo.astro

---
interface Props {
  title: string;
  description?: string;
  authors?: string[];
  published?: string;
  tags?: string[];
  image?: string; // Preferred absolute URL
}

const {
  title,
  description = "",
  authors = [],
  published,
  tags = [],
  image,
} = Astro.props as Props;

const url = Astro.url?.toString?.() ?? "";
const site = (Astro.site ? String(Astro.site) : "") as string;

const ogImage =
  image && image.length > 0
    ? image.startsWith("http")
      ? image
      : site
        ? new URL(image, site).toString()
        : image
    : undefined;

const jsonLd = {
  "@context": "https://schema.org",
  "@type": "Article",
  headline: title,
  description: description || undefined,
  datePublished: published || undefined,
  author: authors.map((name) => ({ "@type": "Person", name })),
  keywords: tags.length ? tags.join(", ") : undefined,
  mainEntityOfPage: url || undefined,
  image: ogImage ? [ogImage] : undefined,
};
---

<title>{title}</title>
<meta name="description" content={description} />
<link rel="canonical" href={url} />

<meta property="og:type" content="article" />
<meta property="og:title" content={title} />
{description && <meta property="og:description" content={description} />}
<meta property="og:url" content={url} />
{
  ogImage && (
    <meta
      property="og:image"
      content={
        "https://HuggingFaceTB-smol-training-playbook.hf.space/thumb.png"
      }
    />
  )
}
{published && <meta property="article:published_time" content={published} />}
{authors.map((a) => <meta property="article:author" content={a} />)}

<meta
  name="twitter:card"
  content={ogImage ? "summary_large_image" : "summary"}
/>
<meta name="twitter:title" content={title} />
{description && <meta name="twitter:description" content={description} />}
{
  ogImage && (
    <meta
      name="twitter:image"
      content={
        "https://HuggingFaceTB-smol-training-playbook.hf.space/thumb.png"
      }
    />
  )
}

<script type="application/ld+json" set:html={JSON.stringify(jsonLd)} />